the f-b-i releasing those suspect pictures just today. we have to stress, at this time, there is no confirmation, as to whether these two incidents might be related. tonights shooting happened on the m.i.t campus. the officer was transported to a nearby hospital but did not survive. everyone in boston understandably on edge after monday's tragedy. we will continue following this story and update you, as necessary, throughout the newcast. as we said, today federal agents did release images of the two suspects believed to be behind the boston marathon bombings. kron 4's grant lodes gives us a closer look at the suspects. >> here is a suspect wanted suspect number two. they released surveillance video of them walking towards the marathon. here are the two suspects. the fbi is referring to them as suspect one and suspect two. suspect one wearing a black hat, suspect two with a backwards white hat. the fbi released surveillance video of the two walking near the marathon finish line. you see suspect one in the black hat walk by, and suspect two